Piezoelectric properties of PCW-PNN-PZT ceramics sintered at low temperature

ABSTRACT

In this study, in order to develop the composition ceramics for ultrasonic sensor application, Pb_0.985Bi_0.01(Co_1/2W_1/2)_0.03(Ni_1/3Nb_2/3)_0.09(Zr_xTi_1-x)_0.88O₃+0.25wt% CuO (abbreviated as PCW-PNN-PZT) system ceramics were prepared with the variations of x and then their phase microstructure, piezoelectric and dielectric characteristics were investigated with the variations of x. The compositions near the morphotropic phase boundary (MPB) appeared when x = 0.495. Moreover, the PCW-PNN-PZT ceramics could be sintered at low temperature of 920°C by adding sintering aids CuO. At sintering temperature of 920°C and x = 0.495 specimen, the density (ρ), electromechanical coupling factor(k_p), dielectric constant (ϵ_r), mechanical quality (Q_m) and piezoelectric constant (d₃₃) piezoelectric figure of merit (d₃₃·g₃₃) indicated the optimal value of 7.94 g/cm³_. 0.65, 1959, 356, 486 pC/N, and 15.56 [pm²/N], respectively, suitable for ultrasonic sensor application. The CuO was proved to lower the sintering temperature of piezoelectric ceramics due to the effects of PbO and CuO liquid phase.

KEYWORDS:

• Low temperature sintering
• piezoelectric figure of merit
• electromechanical coupling factor

Funding

This work was supported by 2015 Sanhak Research Fund of the Small and Medium Business Administration (SMBA).